Journal articles: 'Propanal Spectra'

1

Randell, Jeremy, A. Peter Cox, Kurt W. ii Hillig, Misako Imachi, Marabeth S. LaBarge, and Robert L. Kuczkowski. "Cis and Gauche Propanal: Microwave Spectra and Molecular Structures." Zeitschrift für Naturforschung A 43, no. 3 (March 1, 1988): 271–76. http://dx.doi.org/10.1515/zna-1988-0314.

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The microwave spectra of twelve isotopic species of cis propanal (CH3CH2CHO) and six isotopic forms of the less stable gauche rotamer have been studied to determine accurate structural parameters for both conformers. The following bond lengths (Å) and angles (°) were derived:

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2

Holloway, Thomas T., Billy J. Fairless, Charles E. Freidline, Harry E. Kimball, Robert D. Kloepfer, Charles J. Wurrey, Laleh A. Jonooby, and Harold G. Palmer. "Performance of a Gas Chromatographic-Matrix Isolation-Fourier Transform Infrared Spectrometer." Applied Spectroscopy 42, no. 2 (February 1988): 359–69. http://dx.doi.org/10.1366/0003702884428103.

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The unique matrix-isolated (MI) Fourier transform infrared spectra of diethyl ether, propanal, and trifluoromethane are compared with their vapor-phase spectra. The marked increase in resolution seen in the MI spectra is accompanied by substantial frequency shifts from the peaks in the vapor-phase spectra. The spectra were generated with a gas chromatographic/matrix isolation/Fourier transform infrared spectrometer, with the use of frozen Ar at 13 K as the isolating matrix. The spectra of the 22 isomers of tetrachlorodibenzo- p-dioxin show that each isomer can be distinguished and quantitated at the nanogram level. In addition, preliminary quantitative data were obtained for the pesticides Terbufos® and Fonofos®. Finally, a problem with a previously published spectrum of C-13 2,3,7,8-tetrachlorodibenzo- p-dioxin was uncovered, and it was shown that the spectrum was actually that of C-13 2,3,7-trichlorodibenzo- p-dioxin.

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Yarnall, Yuki Y., Perry A. Gerakines, and Reggie L. Hudson. "Propanal, an interstellar aldehyde – first infrared band strengths and other properties of the amorphous and crystalline forms." Monthly Notices of the Royal Astronomical Society 494, no. 4 (April 18, 2020): 4606–15. http://dx.doi.org/10.1093/mnras/staa1028.

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ABSTRACT Chemical evolution in molecular clouds in the interstellar medium is well established, with the identification of over 200 molecules and molecular ions. Among the classes of interstellar organic compounds found are the aldehydes. However, laboratory work on the aldehydes has scarcely kept pace with astronomical discoveries as little quantitative solid-phase infrared (IR) data have been published on any of the aldehydes, and the same is true for important properties such as density, refractive indices, and vapour pressures. In this paper, we examine the IR spectra of solid propanal (HC(O)CH2CH3, propionaldehyde), along with several physical properties, for both the amorphous and crystalline forms of the compound. The quantitative measurements we report, such as IR intensities and optical constants, will be useful in laboratory investigations of the formation and evolution of propanal-containing ices, will serve as benchmark data for theoretical investigations, and will inform observational studies.

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4

Godunov, I. A., V. N. Alekseev, and M. Badavi. "S1?S0 vibronic spectra and the vapor-state molecular structure of propanal and 2-methylpropanal." Journal of Structural Chemistry 34, no. 1 (1993): 17–21. http://dx.doi.org/10.1007/bf00745396.

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Smeyers, Y. G., M. Villa, V. H. Uc, and A. Vivier-Bunge. "A Theoretical Study of the Methyl and Aldehyde Torsion FIR Spectra in Symmetric Propanal Isotopomers." Journal of Molecular Spectroscopy 201, no. 1 (May 2000): 62–69. http://dx.doi.org/10.1006/jmsp.2000.8068.

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Park, Sung Man, Yu Ran Lee, and Chan Ho Kwon. "Conformational Structures of Neutral and Cationic Pivaldehyde Revealed by IR-Resonant VUV-MATI Mass Spectroscopy." International Journal of Molecular Sciences 23, no. 23 (November 26, 2022): 14777. http://dx.doi.org/10.3390/ijms232314777.

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Pivaldehyde, which is an unwanted by-product released with engine exhaust, has received considerable research attention because of its hydrocarbon oxidations at atmospheric temperature. To gain insight into the conformer-specific reaction dynamics, we investigated the conformational structures of the pivaldehyde molecule in neutral (S0) and cationic (D0) states using the recently invented IR-resonant VUV-MATI mass spectroscopy. Additionally, we constructed the two-dimensional potential energy surfaces (2D PESs) associated with the conformational transformations in the S0 and D0 states to deduce the conformations corresponding to the measured vibrational spectra. The 2D PESs indicated the presence of only the eclipsed conformation in the global minima of both states, unlike those in propanal and isobutanal. However, comparing the IR-dip VUV-MATI spectra from two intense peaks in the VUV-MATI spectrum with the anharmonic IR simulations revealed the correspondence between the gauche conformer on the S0 state and the measured IR spectra. Furthermore, Franck–Condon analysis confirmed that most peaks in the VUV-MATI spectrum are attributed to the adiabatic ionic transitions between the neutral gauche and cationic eclipsed conformers in pivaldehyde. Consequently, electron removal from the highest occupied molecular orbital, consisting of the nonbonding orbital of the oxygen atom in pivaldehyde, promoted the formyl-relevant modes in the induced cationic eclipsed conformer.

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Metha, G. F., M. A. Buntine, D. C. Mcgilvery, and R. J. S. Morrison. "The (n, 3s) Rydberg State in Deuterated Aldehydes: Jet-Cooled MPI Spectra of the Propanal Isotopomeric Series." Journal of Molecular Spectroscopy 165, no. 1 (May 1994): 32–56. http://dx.doi.org/10.1006/jmsp.1994.1109.

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8

Brei, Volodymyr. "OXIDATION OF ALCOHOLS OVER CERIUM-OXIDE CATALYST: CORRELATION BETWEEN THE ACTIVATION ENERGY OF THE REACTION AND THE CHEMICAL SHIFT δ (R13 COH)." Ukrainian Chemistry Journal 85, no. 8 (August 15, 2019): 66–72. http://dx.doi.org/10.33609/0041-6045.85.8.2019.66-72.

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The oxidation of thirteen alcohols over sup-ported CeO2/Al2O3 catalyst with 10 wt.% of CeO2 have been studied using a desorption mass-spec-trometry technique. A catalyst sample 4–6 mg in quartz cuvette was evacuated at 100 0C, cooled to room temperature, and then adsorption of a alco-hol was provided. After vacuumation of alcohol excess, the TPR profiles of products of alcohol oxidation were recorded at sweep rate 2 a.u.m./sec and heating rate of 15 0C/min using MX-7304A monopole mass- spectrometer. Identification of formed aldehydes and ketones was provided on the bases of their characteristic ions in obtained mass-spectra, namely, acetaldehyde (m/e = 29, 44); pro-panal (29, 58); acetone (43, 58); butanal (44, 43); methyl propanal (43, 41, 72), 2-butanon (43, 72); methoxyacetone (45, 43); cyclohexanone (55); ace-tophenone (105, 77); benzaldehyde (77, 106). It was shown that the oxidation of several alcohols pro-ceeds in a wide temperature interval from 130 to 280 0C. So, peak of formaldehyde formation from me-thanol adsorbed on CeO2/Al2O3 is observed at 280 0C whereas peaks of methyl glyoxal and water formation from adsorbed hydroxyacetone are re-corded at 135 0 C. The linear correlation between activation energy of reaction and chemical shift δ (R13COH) of studied alcohols was found as Ea= 183 –1.4δ (kJ/mol). Respectively, the maximum oxi-dation rate, for instance, for methanol (50 ppm) is observed at 280 0C, for ethanol (58 ppm) at 215 0C, for n-butanol (62 ppm) at 200 0C, for n-propanol (64 ppm) at 190 0C, for 2-butanol (69 ppm) at 160 0C, for hydroxyacetone (69 ppm) at 135 0C, and for 1-phenylethanol (70 ppm) at 130 0C. Thus, ability of alcohols to oxidation decreases with increase of their electronic density on carbon atom of alcohol group in following order: 1-phenyl ethanol ≈ hyd-roxyacetone ≈ cyclohexanol > allyl alcohol ≈ 2-bu-anol ≈ i-butanol ≈ i-propanol > methoxypropanol-2 ≈ n-propanol ≈ n-butanol ≈ benzyl alcohol ≈ ethanol >> methanol. On an example of ethanol, the scheme of alcohol oxidation on ceria that assumes the addition of atomic oxygen to C–H bond of alcoho-lic group with intermediate acetaldehyde hydrate formation is discussed.

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9

Demaison, J., H. Maes, B. P. Van Eijck, G. Wlodarczak, and M. C. Lasne. "Determination of the moment of inertia of methyl groups: Analysis of the millimeterwave spectra of cis-propanal and methylthioethyne." Journal of Molecular Spectroscopy 125, no. 1 (September 1987): 214–24. http://dx.doi.org/10.1016/0022-2852(87)90208-6.

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10

METHA, G. F., M. A. BUNTINE, D. C. MCGILVERY, and R. J. S. MORRISON. "ChemInform Abstract: The (n, 3s) Rydberg State in Deuterated Aldehydes: Jet-Cooled MPI Spectra of the Propanal Isotopomeric Series." ChemInform 26, no. 8 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199508036.

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11

Kwaśniewicz, Michał, and Mirosław A. Czarnecki. "The Effect of Chain Length on Mid-Infrared and Near-Infrared Spectra of Aliphatic 1-Alcohols." Applied Spectroscopy 72, no. 2 (November 14, 2017): 288–96. http://dx.doi.org/10.1177/0003702817732253.

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Effect of the chain length on mid-infrared (MIR) and near-infrared (NIR) spectra of aliphatic 1-alcohols from methanol to 1-decanol was examined in detail. Of particular interest were the spectra-structure correlations in the NIR region and the correlation between MIR and NIR spectra of 1-alcohols. An application of two-dimensional correlation analysis (2D-COS) and chemometric methods provided comprehensive information on spectral changes in the data set. Principal component analysis (PCA) and cluster analysis evidenced that the spectra of methanol, ethanol, and 1-propanol are noticeably different from the spectra of higher 1-alcohols. The similarity between the spectra increases with an increase in the chain length. Hence, the most similar are the spectra of 1-nonanol and 1-decanol. Two-dimensional hetero-correlation analysis is very helpful for identification of the origin of bands and may guide selection of the best spectral ranges for the chemometric analysis. As shown, normalization of the spectra pronounces the intensity changes in various spectral regions and provides information not accessible from the raw data. The spectra of alcohols cannot be represented as a sum of the CH3, CH2, and OH group spectra since the OH group is involved in the hydrogen bonding. As a result, the spectral changes of this group are nonlinear and its spectral profile cannot be properly resolved. Finally, this work provides a lot of evidence that the degree of self-association of 1-alcohols decreases with the increase in chain length because of the growing meaning of the hydrophobic interactions. For butyl alcohol and higher 1-alcohols the hydrophobic interactions are more important than the OH OH interactions. Therefore, methanol, ethanol, and 1-propanol have unlimited miscibility with water, whereas 1-butanol and higher 1-alcohols have limited miscibility with water.

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12

Ragouc-Sengler, C., A. Tracqui, A. Chavonnet, J. B. Daijardin, M. Simonetti, P. Kintz, and B. Pileire. "Aldicarb poisoning." Human & Experimental Toxicology 19, no. 12 (December 2000): 657–62. http://dx.doi.org/10.1191/096032700672133218.

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Aldicarb (2 ethyl-2 (methylthio) propanal o-[(methlamino)-carbonyl] oxime) is a pesticide manufactured since 1965. This carbamate ester is sold under the tradename, Temiks, and is used as insecticide and nematicide. The Environmental Protection Agency has classified aldicarb in the highest toxicity category and has defined a strict control for its delivery and use. In Brazil and the Caribbean island, aldicarb is illegally used as a household rodenticide with a widespread risk of poisoning. Our study presents the first review of aldicarb poisoning circumstances associated with cliical and analytical findings. Moreover, the oxime treament is discussed. Eighteen patients with cholinergic symptoms admitted to the Emergency Unit and two deceased with a history of aldicarb poisoning were included in the study. As agricultural workers, only two of them could legally use Temikg. Seventy percent of the patients was managed by the Emergency Mobil Unit. Serum cholinesterase activity was always lower than 30% of the normal range and aldicarb was identified by UV spectra and retention time after liquid chromatogrphy separation. The most common muscarinic effect was diarrhea, the main nicotinic sign fasciculation and almost half of the poisoned patients had central nervous system (CNS) depression (Glasgow Coma Score lower than 8). Four patients had serious conduction abnoralities and two of them died. These results suggest that aldicarb intoxication is always severe. Oxime treatment did not produce side effects and should be recommended whenever the pesticide involved is unknown. Effective measures should be implemented to stamp out the illicit use of aldicarb.

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13

Førland, Geir M., Fred O. Libnau, Olav M. Kvalheim, and Harald Høiland. "Self-Association of Medium-Chain Alcohols in n-Decane Solutions." Applied Spectroscopy 50, no. 10 (October 1996): 1264–72. http://dx.doi.org/10.1366/0003702963904854.

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Self-association of medium-chain alcohols in n-decane solutions has been studied by infrared absorption of the fundamental OH stretching vibration. The alcohols investigated were 1-propanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-butanol, 1-pentanol, and 1-hexanol. Infrared spectra were acquired for varying alcohol molalities, the highest concentration being 0.2 mol/kg. The spectra for each alcohol were collected in a data matrix. The bilinear multicomponent data were successfully resolved into spectra and concentration profiles by a multivariate method. The result indicates that monomers dominate the spectral variance in the low-molality region, while cyclic oligomers dominate in the upper concentration range. It further indicates that minor amounts of open-chain aggregates may be present. The monomer and cyclic tetramer appear to be the dominant species, while the amount of open-chain aggregates was negligible even in the low-molality region. The equilibrium constants for the monomer–tetramer association reactions ( K1–4) were calculated by a least-squares method. The calculated values for the equilibrium constants, based on the molality, range from 138 to 106 for the linear alcohol molecules. The result shows that 1-butanol, 1-pentanol, and 1-hexanol have similar constants, while 1-propanol displays a markedly higher value. The equilibrium constants obtained for 2-methyl-1-propanol and 2-methyl-2-propanol were 77 and 39, respectively. The considerably lower values for the branched alcohol molecules indicate that steric interaction between the chain prevents self-association into larger aggregates.

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Katsumoto, Yukiteru, Daisuke Adachi, Harumi Sato, and Yukihiro Ozaki. "Usefulness of a Curve Fitting Method in the Analysis of Overlapping Overtones and Combinations of CH Stretching Modes." Journal of Near Infrared Spectroscopy 10, no. 1 (January 2002): 85–91. http://dx.doi.org/10.1255/jnirs.325.

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This paper reports the usefulness of a curve fitting method in the analysis of NIR spectra. NIR spectra in the 7500–5500 cm−1 (1333–1818 nm) region were measured for water–methanol, water–ethanol and water–1-propanol mixtures with alcohol concentrations of 0–100 wt% at 25°C. The 6000–5600 cm−1 (1667–1786 nm) region, where the overtones and combinations of CH3 and CH2 stretching modes are expected to appear, shows significant band shifts with the increase in the alcohol content. To analyse the concentration-dependent spectral changes, a curve fitting method was utilised, and the results were compared with those obtained previously by a second derivative method. It was found that the first overtones of CH3 asymmetric and symmetric stretching modes of alcohols show a downward shift by about 15–30 cm−1 with the increase in the concentration of alcohols. The shifts are much larger for water–methanol mixtures than for water–ethanol and water–1-propanol mixtures. The first overtones and combinations of CH2 stretching modes of ethanol and 1-propanol also show a small downward shift. These shifts support our previous conclusion that there is an intermolecular “CH⃛O” interaction between the methyl group and water in the water–alcohol mixtures. The curve fitting method provided more feasible results for the band shifts than the second derivative method. It was revealed from the curve fitting method that the first overtone of the CH3 asymmetric stretching mode of water–methanol, water–ethanol and water–1-propanol mixtures shows different concentration-dependent plots. The first overtone of CH3 asymmetric stretching mode of water–methanol mixtures shifts more rapidly in the high methanol concentration range while that of water–1-propanol concentration shifts more markedly in the low 1-propanol concentration range. That of water–ethanol mixtures shows an intermediate trend. Based upon these differences structural differences among the three kinds of water–alcohol mixtures are discussed.

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Max, Jean-Joseph, Stéphane Daneault, and Camille Chapados. "1-Propanol hydrate by IR spectroscopy." Canadian Journal of Chemistry 80, no. 1 (January 1, 2002): 113–23. http://dx.doi.org/10.1139/v01-198.

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The mid-IR attenuated total reflectance (mid-IRATR) spectra of a series of 1-propanol and water mixtures were obtained. Factor analysis (FA) applied to spectra gave the spectra of three principal species and their abundance: pure water, pure propanol, and a 1-propanol hydrate (1:1). When compared to the pure solvents, the hydrate propanol bands were modified which indicated that the valence bonds were perturbed. The assignment of the hydrate IR bands was made by comparing them with those of pure 1-propanol and pure water. No monomer was observed which indicated that all species were associated. The simplest representation of the different associations is by groups of two on which an intermolecular bond (H-bond) can be placed. The exchange between the molecules can be represented by the following equation: (H2O···H2O) + (CH3CH2CH2OH···OHCH2CH2CH3) [Formula: see text] 2(CH3CH2CH2OH···OH2). The hydrate's formation constant (Kf) is 1.2 (±0.2). This value is less than the one expected from the association of freely moving molecules, indicating that the hydrophobic interactions of the 1-propanol aliphatic chains decrease the strength of the hydrogen bond between water and alcohol in the hydrate.Key words: IR spectroscopy, ATR spectroscopy, 1-propanol, liquid, aqueous solutions, eigenspectra, hydrate, factor analysis.

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Poli, G., M. U. Dianzani, K. H. Cheeseman, T. F. Slater, J. Lang, and H. Esterbauer. "Separation and characterization of the aldehydic products of lipid peroxidation stimulated by carbon tetrachloride or ADP-iron in isolated rat hepatocytes and rat liver microsomal suspensions." Biochemical Journal 227, no. 2 (April 15, 1985): 629–38. http://dx.doi.org/10.1042/bj2270629.

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Carbonyl products were separated and identified in suspensions of rat liver microsomal fractions and in isolated hepatocytes, after stimulation of lipid peroxidation by incubation with the pro-oxidants CCl4 and ADP-iron. The carbonyl products were allowed to react with 2,4-dinitrophenylhydrazine, and the derivatives were extracted and separated by t.l.c. into three zones of non-polar materials, and one fraction of polar derivatives that remained at the origin. Separation of the individual non-polar hydrazones in each zone by h.p.l.c. demonstrated that zone I prepared from microsomal fraction or hepatocytes incubated with CCl4 or ADP-iron contained mainly 4-hydroxyhex-2-enal, 4-hydroxynon-2-enal and 4-hydroxynona-2,5-dienal. Zone III consisted mainly of the alkanals propanal, pentanal and hexanal, the 2-alkenals propenal, pent-2-enal, hex-2-enal, hept-2-enal, oct-2-enal and non-2-enal, the ketones butanone, pentan-2-one and pentan-3-one, and deca-2,4-dienal. Incubation of a microsomal fraction with ADP-iron was much more effective in producing malonaldehyde and other carbonyl products than an incubation with CCl4. Despite such quantitative differences, there were no obvious qualitative differences in the h.p.l.c. spectra obtained from zones I and III. However, the stoichiometric evaluation of fatty acid loss and the production of malonaldehyde and other carbonyls suggests that the pathways of lipid peroxidation triggered by CCl4 and ADP-iron are different. The accumulation of carbonyl products of lipid peroxidation in isolated hepatocytes is strongly affected by their metabolism; in particular, 4-hydroxyalkenals were found to be metabolized very rapidly. Nonetheless, both CCl4 and ADP-iron produced stimulation in the production of malonaldehyde and non-polar carbonyl production. After incubation of rat hepatocytes with CCl4 or ADP-iron it was found that approx. 50% of the total amount of non-polar carbonyls produced during incubation escaped into the external medium. This was not leakage from dead cells, as 90-95% of the hepatocytes had retained their integrity at the end of the incubation. Release of carbonyl products from cells stimulated to undergo lipid peroxidation may be a mechanism for spreading an initial intracellular disturbance to affect critical targets outside the parent cell.

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17

Kafka, Stanislav, Jan Čermák, Tomáš Novák, František Pudil, Ivan Víden, and Miloslav Ferles. "Syntheses of piperazines substituted on the nitrogen atoms with allyl, propyl, 2-hydroxypropyl and 3-hydroxypropyl groups." Collection of Czechoslovak Chemical Communications 50, no. 5 (1985): 1201–11. http://dx.doi.org/10.1135/cccc19851201.

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The paper describes synthesis of 1,4-diallylpiperazine (I), 1-allylpiperazine (III), 1-propylpiperazine (IV), 1-(1-piperazinyl)-2-propanol (V), 3-(1-piperazinyl)-1-propanol (VI), 1-allyl-4-propylpiperazine (VII), 1-(4-allyl-1-piperazinyl)-2-propanol (VIII), 3-(4-allyl-1-piperazinyl)-1-propanol (IX), 1,4-dipropylpiperazine (X), 1-(4-propyl-1-piperazinyl)-2-propanol (XI), 3-(4-propyl-1-piperazinyl)-1-propanol (XII), 1,4-bis(2-hydroxypropyl)piperazine (XIII), 3-[4-(2-hydroxypropyl)-1-piperazinyl]-1-propanol (XIV) and 1,4-bis(3-hydroxypropyl)piperazine (XV). Retention indices of I-XV reported and mass spectra of the compounds are discussed.

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Xu, Shuyu, D. Bruce Chase, John F. Rabolt, and Isao Noda. "Two-Dimensional Correlation Spectroscopy (2D-COS) Studies of Solution Mixtures in the Low Frequency Raman Region." Applied Spectroscopy 73, no. 9 (May 20, 2019): 1012–18. http://dx.doi.org/10.1177/0003702819848501.

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Raman spectra of a series of binary solution mixtures, including chloroform (CHCl3), ethanol (EtOH), and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), were analyzed using the two-dimensional correlation spectroscopic (2D-COS) technique in the low frequency region. Numerous asynchronous cross-peaks ubiquitously appeared in the concentration-dependent Raman spectra of these organic solvent mixtures. The result clearly demonstrated a deviation from ideal solution behavior, reflecting the presence of specific molecular interactions causing a subtle nonlinear spectral intensity response of Raman bands to the concentration changes. Furthermore, the combination of 2D-COS and low frequency Raman spectroscopy was extended to poly[(R)-3-hydroxybutyrate- co-(R)-3-hydroxyhexanoate] (PHBHx) copolymer solutions in CHCl3-HFIP co-solvents. The results suggest the existence of hydrogen bonding interaction between the PHBHx and HFIP, which is consistent with the previous infrared spectroscopic study of PHBHx solutions.

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Vikhrova, S. V., O. L. Rutenberg, A. V. Smirnov, A. E. Petukhov, and T. O. Barinskaya. "Improvement of methods and means of measuring the content of toxicants in biological objects." Journal of Physics: Conference Series 2192, no. 1 (March 1, 2022): 012013. http://dx.doi.org/10.1088/1742-6596/2192/1/012013.

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Abstract The results of the development of a reference procedure for measuring the content of toxicants in biological objects are considered. To ensure traceability to the state primary standard, two types of certified reference materials of aqueous solutions of propanol-1 and propanol-2 have been developed, manufactured and approved. The mass spectra of narcotic psychotropic and psychoactive medicinal substances with fixed retention times were investigated. Mass spectra tables have been approval as standard reference data.

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Michniewicz, N., A. S. Muszyński, W. Wrzeszcz, M. A. Czarnecki, B. Golec, J. P. Hawranek, and Z. Mielke. "Vibrational spectra of liquid 1-propanol." Journal of Molecular Structure 887, no. 1-3 (September 2008): 180–86. http://dx.doi.org/10.1016/j.molstruc.2008.03.020.

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Ydoshida, Koji, and Toshio Yamaguchi. "Low-frequency Raman Spectroscopy of Aqueous Solutions of Aliphatic Alcohols." Zeitschrift für Naturforschung A 56, no. 8 (August 1, 2001): 529–36. http://dx.doi.org/10.1515/zna-2001-0801.

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Abstract Low-frequency Raman spectra have been measured at room temperature as functions of the alcohol mole fraction in aqueous solutions of methanol, ethanol, 1-propanol, 2 -propanol, and /er/-butylalcohol (TBA). Intrinsic Raman spectra R (ῡ) were obtained from depolarized Rayleigh wing spectra. Isosbestic points have been observed in R (ῡ) of the aqueous solutions of ethanol, 1-propanol, and 2 -propanol, suggesting that the structure o f the solutions is characterized by individual alcohol aggregates and water clusters without a significant amount of alcohol-water mixed aggregates. The R (ῡ) spectra have been expressed as R (ῡ ,x ) = w R (ῡ ,0 ) + aR(D, 1), where R(ῡ, 0) and R(ῡ, 1) are those for pure water and pure alcohols, respectively, and x is the mole fraction of alcohols. The coefficients w and a show the inflection points at characteristic alcohol mole fractions, where microhetrogeneity and structural transition of the solvent clusters take place, as previously shown by X-ray diffraction. In the aqueous solutions of methanol, where no microhetrogeneity takes place, no clear isosbestic point in R(ῡ) has been observed. For aqueous solutions of TBA, an isosbestic point in R(ῡ) has appeared when xTBA > 0.05. Two inflections points in the coefficients have been observed at xTBA « 0.1 and 0.35; the former composition corresponds to the transition composition from the TBA-TBA intermolecular contact to the TBA water molecular association, as previously reported by neutron diffraction.

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Wang, Yan, Yang Qiao Liu, Jing Sun, and Lian Gao. "Debundling of Single Walled Carbon Nanotubes by HPC in 1-Propanol and Water." Materials Science Forum 695 (July 2011): 215–18. http://dx.doi.org/10.4028/www.scientific.net/msf.695.215.

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A novel surfactant, hydroxypropyl cellulose (HPC), was firstly used to debundle Meijo single walled carbon nanotubes (SWNTs) in distilled water and 1-propanol. As comparison, common surfactants (SDBS and Triton) were used to disperse Meijo SWNTs in 1-propanol and distilled water. And the dispersibility of mixed surfactants, HPC/SDBS and HPC/Triton, were also tested. After short ultrasonication and centrifugation, stable supernatant of HPC-SWNTs has been obtained, and HPC show the best dispersibility to Meijo SWNTs. The HPC-SWNTs solution was used to prepare transparent conductive films on PET substrate by spray coating method. After being soaked in 1-propanol and HNO3, the sheet resistance decreased from 8,440 Ω/□ to 4,175Ω/□ at 90% transmittance. TEM, UV-Vis-NIR spectra, and Raman spectra were performed to characterize the SWNT solutions and films.

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Mizukami, Masashi, and Kazue Kurihara. "Hydrogen-Bonded Macrocluster Formation of 1-Propanol and 2-Propanol on Silica Surfaces." Australian Journal of Chemistry 56, no. 10 (2003): 1071. http://dx.doi.org/10.1071/ch03127.

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We have investigated the adsorption of 1- and 2-propanol on silica surfaces from their mixtures with cyclohexane using a combination of colloidal probe atomic force microscopy, adsorption excess isotherms, and FTIR spectroscopy in the ATR mode. The adsorption isotherm indicated that a similar amount of each alcohol was adsorbed on the silica surfaces. FTIR spectra revealed that 1-propanol adsorbed on the surface employing hydrogen-bonding between the surface silanol groups and the hydroxyl groups of 1-propanol as well as between the hydroxyl groups of 1-propanol in the form of a linear zig-zag structure. This structure is similar to the linear hydrogen-bonded structure of ethanol, which we have found on silica and called a ‘surface molecular macrocluster’ (M. Mizukami, M. Moteki, K. Kurihara, J. Am. Chem. Soc. 2002, 124, 12 889). The contact of adsorbed layers of 1-propanol on the opposed silica surfaces brought about the long-range attraction extending to 69 ± 9 nm at 0.1 mol-% 1-propanol. 2-Propanol was also adsorbed on the surface by the hydrogen-bonding, however, in the form of a cyclic structure. No long-range attraction was observed in the 2-propanol/cyclohexane binary liquids at 0.1–6.0 mol-%. The absence of a long-range attraction can be explained by the cyclic aggregation structure of 2-propanol on the surface.

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Mahajan, R. K., Neelam Gupta, and Satinder K. Uppal. "1H NMR spectra of some juvabione analogues." Collection of Czechoslovak Chemical Communications 50, no. 3 (1985): 690–96. http://dx.doi.org/10.1135/cccc19850690.

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A number of aromatic aza-analogues of juvabione and dehydrojuvabione have been synthetized by treatment of substituted benzylamine with 3-methylbutanoyl chloride and 3-methyl-2-butenoyl chloride. Reaction of substituted phenoxyacetyl chlorides with isopropylamine and 2-propanol gives other series of aromatic juvabione analogues. The 1H NMR spectra of some analogues are discussed.

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25

Peng, Shu Ge, Jun Na Liu, Xiao Fei Liu, Yu Qing Zhang, and Jun Zhang. "PVP Stabilized Ruthenium (0) Nanorods as Effective Catalysts in Hydrogen Generation from the Hydrolysis of Sodium Borohydride." Advanced Materials Research 197-198 (February 2011): 1577–81. http://dx.doi.org/10.4028/www.scientific.net/amr.197-198.1577.

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Poly (N-vinyl-2-pyrrolidone) (PVP) - stabilized ruthenium (0) nanorods have been successfully synthesized by refluxing ruthenium (Ⅲ) chloride (RuCl3) in low boiling point alcohols (including ethanol, n-propanol, and n-butanol) using microwave heating for the first time. The effects of low boiling point alcohols on the preparation and catalytic property of ruthenium nanorods were discussed. UV-Vis absorption spectra indicated ruthenium nanorods could be synthesized in n-butanol after 2 h refluxing, far below the refluxing time in ethanol and n-propanol. The activation energy of the hydrolysis of NaBH4 catalyzed by Ruthenium (0) nanorods obtained in ethanol, n-propanol, and n-butanol were determined to be 41.1, 33.3, and 27.9 kJ / mol, respectively.

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26

Zhu, Yong, and Keisaku Kimura. "Electronic Spectra of Si Nanocolloids in 2-Propanol." Chemistry Letters 24, no. 8 (August 1995): 643–44. http://dx.doi.org/10.1246/cl.1995.643.

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27

Takagi, Y., T. Yano, M. Mikami, and S. Kojima. "Temperature dependence of depolarized spectra in n-propanol." Physica B: Condensed Matter 263-264 (March 1999): 306–9. http://dx.doi.org/10.1016/s0921-4526(98)01229-0.

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28

Turan, Nevin, and Kenan Buldurun. "Synthesis, characterization and antioxidant activity of Schiff base and its metal complexes with Fe(II), Mn(II), Zn(II), and Ru(II) ions: Catalytic activity of ruthenium(II) complex." European Journal of Chemistry 9, no. 1 (March 31, 2018): 22–29. http://dx.doi.org/10.5155/eurjchem.9.1.22-29.1671.

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The synthesis, spectral, catalytic and antioxidant properties of ethyl-2-(2-hydroxy-3-methoxybenzylideneamino)-6-methyl-4,5,6-tetrahydrobenzo[b]thiophene-3-carboxylate (L) substituted iron(II), manganese(II), zinc(II), and ruthenium(II)-arene chlorides are described for the first time. The ligand and its metal complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, and spectral (1H NMR, 13C NMR, FT-IR, UV-Vis and Mass) techniques. The FT-IR spectra showed that the ligand can act as bidentate or tridentate. Magnetic moments and electronic spectral studies revealed an octahedral geometry for all the complexes obtained. The thermal behavior of the complexes showed that the water molecules were separated in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. Ru(II) complex was used as catalysts for the transfer hydrogenation of ketones. At the same time, the effect of various bases such as NaOH, KOH, KOBut and NaOAc as organic base were investigated in the transfer hydrogenation of ketones by 2-propanol as the hydrogen source. The complexes and ligand were tested in vitro for their antioxidant activity. The experimental results showed that Ru(II) complex had more potent antioxidant activities than Zn(II), Fe(II), Mn(II) complexes and parent ligand.

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29

Gu, Haiyang, Chen Sun, Rong Wang, Shuangjie Zhu, Yining Dong, Riqin Lv, Xingyi Huang, Yanhui Sun, and Quansheng Chen. "Metalloporphyrin-Based Fluorescent Sensor for the Discrimination of Volatile Organic Compounds Using Density Functional Theory." Journal of Nanoelectronics and Optoelectronics 17, no. 2 (February 1, 2022): 243–50. http://dx.doi.org/10.1166/jno.2022.3190.

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This spectral property of the fluorescent sensors were investigated using density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The considered silver porphyrin (AgP) was selected as a representative dye for the theoretical study of the fluorescent sensors. The molecular structures of AgP and its complexes were optimized at B3LYP/LANL2DZ basis set. The calculated geometry structures, front-line molecular orbitals, absorption spectra, and electronic structures were analyzed to reveal the molecular reaction between AgP-based fluorescent sensors and volatile organic compounds (VOCs). The energy gaps indicated that the efficient orders of AgP-based fluorescent sensor reacted with volatile organic compounds were shown as O2 < N2 < propane (L3) < propaldehyde (L5) < H2S < propanol (L2) < trimethylamine (L1) < ethyl acetate (L6) < butanone (L4). The calculated results all reveal that the AgP-based fluorescent sensor possesses significant changes (i.e., molecular structure, frontline molecular orbital, and absorption spectra) before and after reacting with volatile organic compounds, which are closely related to the selectivity and sensitivity property of AgP-based fluorescent sensor. Therefore, this study may be useful for the AgP-based fluorescent sensor in a special application region.

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30

Doroshenko, Irina, Valeriy Pogorelov, and Valdas Sablinskas. "Infrared Absorption Spectra of Monohydric Alcohols." Dataset Papers in Chemistry 2013 (October 24, 2013): 1–6. http://dx.doi.org/10.7167/2013/329406.

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FTIR spectra of homologous series of monohydric alcohols which belong to the class of partly ordered liquids were registered. The molecules of monohydric alcohols containing hydroxyl group are able to form hydrogen-bonded clusters in the condensed phase. The existence of clusters is clearly observed from the position and the contour of the stretch OH band in the vibrational spectra of liquid alcohols. In this work, the experimentally registered FTIR spectra of liquid n-alcohols from methanol to decanol are presented as well as the same spectra of methanol, ethanol, propanol, butanol, pentanol, and hexanol in gas phase.

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31

Doroshenko, I., Ye Vaskivskyi, Ye Chernolevska, L. Meyliev, and B. Kuyliev. "Molecular Isomerization in n-Propanol Dimers." Ukrainian Journal of Physics 65, no. 4 (April 17, 2020): 291. http://dx.doi.org/10.15407/ujpe65.4.291.

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The molecular isomerization has been studied in n-propanol dimers by quantum-chemical calculations with the DFT method. 25 combinations of molecular pairs are calculated with and without consideration of the dielectric constant of n-propanol. Such approach allowed us to determine the most stable configurations of alcohol dimers. It has been shown that dimers of n-propanol are mostly (77.1%) formed by only 5 of 25 possible configurations at room temperature and by 2 combinations (87.3%) at the melting point. The size distribution of dimers and the spectral dispersion in the region of free and bonded O–H stretching vibrations are calculated.

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32

Базыль, О. К., Е. Н. Бочарникова, О. Н. Чайковская, В. С. Чайдонова, and Г. В. Майер. "Спектральные и протоноакцепторные свойства хлорамфеникола." Оптика и спектроскопия 130, no. 11 (2022): 1638. http://dx.doi.org/10.21883/os.2022.11.53768.3721-22.

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The absorption spectra of chloramphenicol aqueous solution were obtained experimentally. The absorption spectra of chloramphenicol isomers and the effect on the spectra of the formation of H-bonded complexes were calculated and interpreted using quantum chemistry methods. Calculation results showed that the absorption spectrum of chloramphenicol by position of bands and their nature is largely determined by the nitrobenzene fragment with little participation of propanol and dichloroacetamide fragments of chloramphenicol. The proton acceptor properties of individual chloramphenicol fragments and the effect of the formation of H-bonded complexes on them have been analyzed.

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33

Czarnecki, Mirosław Antoni, and Michał Kwaśniewicz. "Effect of the chain length on near-infrared spectra of 1-alcohols from methanol to 1-decanol." NIR news 30, no. 3 (March 7, 2019): 6–8. http://dx.doi.org/10.1177/0960336019836861.

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This work shows the effect of the chain length on near-infrared spectra of 1-alcohols and is based on a recent paper by Kwaśniewicz and Czarnecki ( Appl Spectrosc 2018, 72: 288). Near-infrared spectra of 1-alcohols from methanol to 1-decanol in the pure liquid phase were recorded from 5200 to 9000 cm−1. The similarities and differences between the spectra were analyzed by the classical and chemometric methods (principal component analysis). The obtained results reveal that the near-infrared spectra of methanol, ethanol, and 1-propanol are appreciably different from the spectra of higher 1-alcohols. As shown, the degree of self-association of 1-alcohols decreases with the increase in the chain length.

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34

Voitiuk, O. D., A. V. Yegorova, Yu V. Scrypynets, S. N. Kashutskуy, and V. P. Antonovich. "Luminescent determination of residues of trazodon hydrochloride and melatonin after cleaning pharmaceutical equipment." Farmatsevtychnyi zhurnal, no. 4 (September 10, 2019): 73–81. http://dx.doi.org/10.32352/0367-3057.4.19.08.

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A prerequisite for ensuring the quality of medicines is their production in accordance with the rules of GMP (Good Manufacturing Practice for Medicinal Products), one of the most important requirements of which is equipment cleaning. In many cases, the same equipment is used in the production of various preparations. Therefore, to prevent contamination of each of the following drugs, the previous one, it is very important to carry out an effective equipment cleaning procedure with a mandatory assessment of its purity. The purpose of this study was to develop simple, express, selective methods for luminescent determination of residual quantities of APIs of trazodone hydrochloride (TG) and melatonin (MT) in washes to control the completeness of their removal when cleaning process equipment. The excitation and luminescence spectra were recorded using a Cary Eclipse "Varian" spectrofluorimeter (Australia) with a xenon lamp 150 W. Electronic absorption spectra were recorded on a UV-2401 PC spectrophotometer «Shimadzu» (Japan). The electronic absorption spectra of TG and MT have absorption bands in the UV spectral region. It was established experimentally that the excitation spectra of TG and MT are similar to their absorption spectra (λex = 318 nm (TG) and λem = 274 nm (MT)). The effect on the luminescence intensity of TG and MT of methanol, ethanol, acetonitrile, dimethylformamide, dimethylsulfoxide, propanol (50 v/v) was studied. It is established that the maximum luminescence is observed in water. The methods were validated according to the following parameters: specificity, linearity, accuracy, limit of quantitation. The degree of extraction of trazodone hydrochloride and melatonin from applicators and surfaces of pharmaceutical equipment is more than 90%. The developed methods can be recommended for determining the residual amounts of trazodone hydrochloride and melatonin while monitoring the quality of the cleaning of pharmaceutical equipment.

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35

Beć, Krzysztof B., Yoshisuke Futami, Marek J. Wójcik, and Yukihiro Ozaki. "A spectroscopic and theoretical study in the near-infrared region of low concentration aliphatic alcohols." Physical Chemistry Chemical Physics 18, no. 19 (2016): 13666–82. http://dx.doi.org/10.1039/c6cp00924g.

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The near-infrared (NIR) spectra of low-concentration (5 × 10⁻³ M) solutions in CCl₄ of basic aliphatic alcohols, methanol, ethanol, and 1-propanol were, for the first time, calculated by second-order vibrational perturbation theory computations and were compared with the corresponding experimental data.

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36

HUANG, YAO, XIANG-YUAN LI, KE-XIANG FU, and QUAN ZHU. "NEW FORMULATION FOR NON-EQUILIBRIUM SOLVATION: SPECTRAL SHIFTS AND CAVITY RADII OF 6-PROPANOYL-2-(N,N-DIMETHYLAMINO) NAPHTHALENE AND 4-(N,N-DIMETHYLAMINO) BENZONITRILE." Journal of Theoretical and Computational Chemistry 05, spec01 (January 2006): 355–74. http://dx.doi.org/10.1142/s0219633606002313.

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In the present work, the new formulations describing spectral shifts by the authors have been introduced and employed to investigate two dye molecules, 6-propanoyl-2-(N,N-dimethylamino) naphthalene and 4-(N,N-dimethylamino) benzonitrile. From the viewpoints of the authors, the cavity radii were overestimated owing to the errors existing in the traditional models. Slightly differing from the results by other authors in the past, this work fits the cavity radii to the values of ~4.5 Å for 6-propanoyl-2-(N,N-dimethylamino) naphthalene and ~3.2 Å for 4-(N,N-dimethylamino) benzonitrile. In the fittings, both point dipole approximation and multipole expansion methods are employed. The calculations of the excited states are performed by means of the time-dependent density functional theory. Comparing the fitted cavity radii from the experimental spectra with those estimated from the molecular volumes by some well-known procedures such as COSMO and PCM, we find that the new formulations give fairly satisfactory results. By taking an atomic ion as an example, the authors argue that the Onsager radii recommended by some popular procedures are greatly exaggerated. The cavity radius derived simply from the volume encompassed by the solvent-accessible surface, without any addition of other parts, is suggested for application.

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37

Kalichkina, L. E., A. A. Bakibaev, and V. S. Malkov. "Spectral study of thione-thiol tautomerization of thiourea in aqueous alcohol solution." Bulletin of the Karaganda University. "Chemistry" series 99, no. 3 (September 30, 2020): 66–71. http://dx.doi.org/10.31489/2020ch3/66-71.

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In this work we studied the equilibrium of thione–thiol tautomerization by Raman and UV spectroscopies. This type of tautomerization influences on the course and direction of the reaction between thiourea and other organic compounds. The studies were carried out in water and aqueous alcohol medium. Мethanol, ethanol, propanol-1 and propanol-2 were used as alcohols. Hydrochloric acid was used to protonate thiourea in water and aqueous alcoholic solutions. UV spectroscopy made it possible to establish the tautomer ratio in water and aqueous alcohol solutions as the ratio of the intensities of absorption bands at 236 and 200 nm. There is an increase in the content of the thiol form and a decrease of the thione form observed in the row water-methanol-ethanol-propanol-isopropyl alcohol. The addition of hydrochloric acid to the thiourea water or aqueous alcohol solutions leads to the increase of the thione form and to the decrease of the thiol form in the composition. The thione form of thiourea can be determine by Raman spectra of –C=S group. The thiol form of thiourea is difficult to detect by Raman spectroscopy due to the overlap of the –S–H bond absorption band with alcohols absorption bands.

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38

Kutschy, Peter, Ján Imrich, Juraj Bernát, Pavol Kristian, and Iveta Fedoriková. "A study of photocyclization of O-alkyl N-(3-chloro-2-benzo[b]thienocarbonyl)monothiocarbamates." Collection of Czechoslovak Chemical Communications 51, no. 9 (1986): 2002–12. http://dx.doi.org/10.1135/cccc19862002.

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The O-alkyl N-(3-chloro-2-benzo[b]thienocarbonyl)monothiocarbamates prepared by the reaction of 2-isothiocyanatocarbonyl-3-chlorobenzo[b]thiophene with methanol, ethanol, 1-propanol, and 2-propanol are cyclized on irradiation with light of the wavelength above 300 nm to give high yields (80-90%) of 2-alkoxy-4H-benzo[b]thieno[2,3-e]-1,3-thiazin-4-one derivatives. From the absorption and emission spectra of the starting compounds as well as from a study of model compounds and influence of the reaction conditions it is presumed that the investigated intramolecular photosubstitution of chlorine by sulphur proceeds from the first singlet excited state (π, π*) by a radical mechanism through the phase of radical complex formation.

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39

Khmelnitsky, Yurii L., Alexander K. Gladilin, Irina N. Neverova, Andrei V. Levashov, and Karel Martinek. "Detergentless microemulsions as media for enzymatic reactions: Catalytic properties of laccase in the ternary system hexane-2-propanol-water." Collection of Czechoslovak Chemical Communications 55, no. 2 (1990): 555–63. http://dx.doi.org/10.1135/cccc19900555.

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The catalytic activity and stability of laccase in the detergentless ternary system hexane - 2-propanol - water were studied. In the microemulsion region of the phase diagram the enzyme exhibited the highest catalytic activity and stability, which were comparable to those in aqueous solution. The character of the microenvironment inside microemulsion droplets was studied using nitrate anion as spectral probe and its polarity was found to correspond to that of 75% v/v aqueous 2-propanol. In principle, laccase can be recovered many times from the microemulsion without loss of catalytic activity.

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40

Yağcı, Çiğdem, and Ahmet Bilgin. "Synthesis and characterization of novel tetrakis (3-hydroxypropylmercapto)-substituted phthalocyanines." Journal of Porphyrins and Phthalocyanines 17, no. 06n07 (June 2013): 573–86. http://dx.doi.org/10.1142/s1088424613500697.

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A phthalonitrile precursor 4-(3-hydroxypropylmercapto)phthalonitrile (3) was synthesized via a base-catalyzed nucleophilic aromatic nitro displacement of 4-nitrophthalonitrile with the 3-mercapto-1-propanol. A novel tetrasubstituted metal-free phthalocyanine (4) ( M = 2 H ) and its metal complexes (5–8) ( M = Zn , Ni , Cu and Co ) bearing 3-hydroxypropylmercapto moieties were prepared by the cyclotetramerization reaction of (3) with the appropriate materials. The visible spectra of the zinc(II) phthalocyanine (5) was recorded with different concentrations and different ions as Ag +, Hg 2+ and Pb 2+ in DMF and also with different solvents as dimethylformamide and pyridine. Fluorescence spectrum of the compound (5) was also studied. Temperature and frequency dependence of AC conductivity for (4–8) was investigated in air and under vacuum and were found to be ~10-8–10-5 S.m-1. Thermal properties of the phthalocyanines were examined by differential scanning calorimetry. All the novel compounds have been characterized by elemental analysis, UV-vis, FT-IR, NMR and MS spectral data and DSC techniques.

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41

Aaron, J. J., M. D. Gaye, C. Párkányi, C. Boniface, T. W. N. Bieze, S. S. Atik, K. S. Raghu Veer, L. von Szentpály, and R. Ghosh. "Solvent Effects upon the Electronic Absorption and Fluorescence Spectra of Pteridines and Riboflavin and Their Ground and First Excited Singlet State Dipole Moments." Pteridines 3, no. 3 (September 1991): 153–63. http://dx.doi.org/10.1515/pteridines.1991.3.3.153.

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The electronic absorption. fluorescence excitation, and fluorescence emission spectra of a series of pteridines (lumazine, xanthopterin, isoxanthopterin, biopterin) and riboflavin (vitamin B2) were measured at room temperature (298 K) in a number of solvents covering a wide range of polarities (dioxane, ethyl ether, chloroform, ethyl acetate, 1-butanol. 2-propanol, ethanol, methanol, dimethylformamide, acetonitrile, and dimethyl sulfoxide). The effects of the solvent upon the spectral properties are discussed. Experimental groundstate dipole moments were measured for selected compounds and were used in combination with the spectral data to evaluate their first excited singlet-state dipole moments by means of the solvatochromic shift method (Bakhshiev's and Kawski-Chamma-Viallet's equations based on the variation of the Stokes shift with the solvent dielectric constant-refractive index term). The theoretical ground and excited singlet-state dipole moments for all pteridines and riboflavin were calculated as a vector sum of the π-component (obtained by the PPP method) and the a-component (obtained from a-bond moments). A second set of theoretical values was obtained by using the CNDO/2method. A good agreement was observed between the experimental and the theoretical values. Excited singlet-state dipole moments are higher than the ground state values by 1 to 6 Debye units for all the pteridines under study with the exception of xanthopterin.

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42

Mikuriya, Masahiro, Satoshi Kurahashi, Seiki Tomohara, Yoshiki Koyama, Daisuke Yoshioka, Ryoji Mitsuhashi, and Hiroshi Sakiyama. "Synthesis, Crystal Structures and Magnetic Properties of Mixed-Valent Tetranuclear Complexes with Y-Shaped MnII2MnIII2 Core." Magnetochemistry 5, no. 1 (January 28, 2019): 8. http://dx.doi.org/10.3390/magnetochemistry5010008.

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Tetranuclear MnII2MnIII2 complexes with 1,3-bis(5-bromo-3-metoxysalicylidenaminomethyl)-2-propanol (H3bmsap) and 1,3-bis(5-chloro-3-methoxysalicylidenaminomethyl)-2-propanol (H3cmsap), [Mn4(bmsap)2(CH3CO2)3(CH3O)] (3) and [Mn4(cmsap)2(CH3CO2)3(CH3O)] (4), were synthesized and characterized by elemental analysis, infrared and diffused reflectance spectra and variable-temperature magnetic susceptibility measurements in the 2–300 K range. The crystal structures of 3 and 4 revealed a Y-shaped tetranuclear manganese cluster formed by the two Schiff-base ligands, three kinds of acetato ligands (bidentate, syn–anti-bridging, and syn–syn-bridging), and µ-methoxido ligand. The magnetic data showed the magnetic interactions among the four manganese atoms are antiferromagnetic as a whole within the tetranuclear cluster.

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43

Bobrowski, A., A. Kmita, M. Starowicz, B. Hutera, and B. Stypuła. "Effect of Magnesium Oxide Nanoparticles on Water Glass Structure." Archives of Foundry Engineering 12, no. 3 (September 1, 2012): 9–12. http://dx.doi.org/10.2478/v10266-012-0073-2.

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Abstract An attempt has been made to determine the effect of an addition of colloidal suspensions of the nanoparticles of magnesium oxide on the structure of water glass, which is a binder for moulding and core sands. Nanoparticles of magnesium oxide MgO in propanol and ethanol were introduced in the same mass content (5wt.%) and structural changes were determined by measurement of the FT-IR absorption spectra.

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44

Bartoš, Josef, Silvia Arrese-Igor, Helena Švajdlenková, Angela Kleinová, and Angel Alegría. "Dynamics of Confined Short-Chain alkanol in MCM-41 by Dielectric Spectroscopy: Effects of matrix and system Treatments and Filling Factor." Polymers 12, no. 3 (March 7, 2020): 610. http://dx.doi.org/10.3390/polym12030610.

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The dynamics of n-propanol confined in regular MCM-41 matrix with the pore size Dpore = 40 Å, under various matrix conditioning and sample confining conditions, using broadband dielectric spectroscopy (BDS), is reported. First, various drying procedures with the capacitor filling under air or N2 influence the BDS spectra of the empty MCM-41 and the confined n-PrOH/MCM-41 systems, but have a little effect on the maximum relaxation time of the main process. Finally, various filling factors of n-PrOH medium in the optimally treated MCM-41 system lead to unimodal or bimodal spectra interpreted in terms of the two distinct dynamic phases in the confined states.

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45

Yusoff, Nurul Huda, Muhamad Mat Salleh, and Muhammad Yahaya. "Room Temperature Fluorescence Gas Sensor Based on Coated TiO₂Nanoparticles." Key Engineering Materials 543 (March 2013): 373–76. http://dx.doi.org/10.4028/www.scientific.net/kem.543.373.

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Room temperature fluorescence gas sensor was developed based on TiO2 nanoparticles coated with porphyrin dye thin films. The porphyrin dye used for this experiment were Iron (III) meso-tetraphenylporphine chloride (IMTPPCl) and Manganase (III) 5,10,15,20 tetra (4-pyridyl)-21H, 23H porphine chloride tetrakis (metachloride). The sensing sensitivity was due to the changes of the emission spectra produce by the thin film when expose to the organic vapors from volatile organic compounds; ethanol, acetone and 2-propanol. Both thin films show good response toward volatile organic vapors. However, TiO2 nanoparticles with porphyrin; IMTPPCl thin film shows pronounced interaction, marked fluorescence spectra and more selective property, hence useful for chemical identification purpose.

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46

Catone, D., S. Turchini, G. Contini, N. Zema, S. Irrera, T. Prosperi, M. Stener, D. Di Tommaso, and P. Decleva. "2-amino-1-propanol versus 1-amino-2-propanol: Valence band and C 1s core-level photoelectron spectra." Journal of Chemical Physics 127, no. 14 (October 14, 2007): 144312. http://dx.doi.org/10.1063/1.2798113.

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47

Fridgen, Travis D., Luke MacAleese, Terry B. McMahon, Joel Lemaire, and Philippe Maitre. "Gas phase infrared multiple-photon dissociation spectra of methanol, ethanol and propanol proton-bound dimers, protonated propanol and the propanol/water proton-bound dimer." Physical Chemistry Chemical Physics 8, no. 8 (2006): 955. http://dx.doi.org/10.1039/b516661f.

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48

Sardarly, А. М. "PHASE COMPOSITION AND OXIDATION DEGREE OF VANADIUM IN CATALYSTS FOR OXIDATIVE DEHYDROGENATION OF PROPANE." Chemical Problems 20, no. 4 (2022): 358–65. http://dx.doi.org/10.32737/2221-8688-2022-3-358-365.

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The phase composition of vanadium and vanadium-antimony-containing samples of γ-Al2O3 and the degree of oxidation of vanadium in them were examined by XRD and EPR methods, respectively. The data of XRD and EPR spectroscopy show the formation of highly dispersed vanadium-oxygen and vanadiumantimony-oxygen structures on the surface of the support. It is shown that the EPR spectra of the studied samples are due to "isolated" vanadium ions with an oxidation state of +4 in nonstoichiometric vanadium-oxygen and vanadium-antimony-oxygen formations with a square pyramid local environment structure with a characteristic V=O double bond. The EPR spectra of two types of paramagnetic centers of vanadium, which differ in the distortion of the square-pyramidal structure of the local environment of the vanadium ion, were identified. It was established that the number of ions with an oxidation state of +4 in V,Sb-containing samples depends on the V/Sb ratio in them.

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49

Du, Xin-Zhen, Yong Zhang, Xian-Zhi Huang, Yun-Bao Jiang, Yao-Qun Li, and Guo-Zhen Chen. "Intense Room-Temperature Phosphorescence of 1-Bromonaphthalene in Organized Media of Beta-Cyclodextrin and Triton X-100." Applied Spectroscopy 50, no. 10 (October 1996): 1273–76. http://dx.doi.org/10.1366/0003702963904999.

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In aerated aqueous solution, intense room-temperature phosphorescence (RTP) of 1-bromonaphthalene (1-BrN) is observed with an host–guest inclusion complex composed of Triton X-100, 1-BrN, and beta-cyclodextrin (β-CD). Triton X-100 is incorporated into the hydrophobic cavity of β-CD as the second guest molecule, and a 1:1:1 ternary complex is formed. This complex, with a polar head group, can be well distributed in aqueous solution, and stable RTP is obtained. Ethanol further enhances the RTP of the ternary complex, whereas 1-propanol and 1-butanol greatly attenuate RTP. Spectral analyses indicate that 1-BrN in the β-CD cavity is replaced by 1-propanol and 1-butanol.

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50

Kafi, Dhaidan Kh. "Theoretical and Experimental Study on Molecular Docking, Spectral and Electronic Properties of N,N-Bis (Salysylaldehyde-2,3-Diamino-1-Propanol) Nanostructure." Research Journal of Chemistry and Environment 26, no. 12 (November 25, 2022): 124–33. http://dx.doi.org/10.25303/2612rjce1240133.

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Abstract:

In this study, theoretical and experimental properties (Structural, Spectral and Electronic Properties) and molecular docking of N,N- bis (salysylaldehyde-2,3- Diamino-1-propanol) molecule were studied. Timedependent density functional theory (TDDFT) and density functional theory (DFT) are employed for the theoritcal calculation. The composite's spectroscopic surveys were conducted using Proton nuclear magnetic resonance, FT-IR and UV/Vis spectroscopy techniques. The 1H NMR spectra for proton nuclear magnetic resonance have been examined with DMSO4 solvent. The FT-IR spectrum in rigid situation has been calculated to be between 4000-400 cm-1. The absorption spectra intensity of the composite with ethanol has been calculated to be between 200 and 800 nm. Scanning electron microscope (SEM) image has been study. Results demonstrated that the compound scanning electron microscopy image resembled a sphericals with particle size of 50 nm. The data structure, vibrational central modes, UV/V spectrum with 1H NMR isotropic chemical shifts of this molecule in the ground state were assessed utilizing the theory of functional density (thus DFT) and the B3LYP/6- 311G(d,p) basis group. The energies of reorganization for the hole and the electron have also been calculated. Finally, the assessment between the data of experiment and the results that have been calculated showed a good agreement. The inhibitory potential of the investigated compound was assessed against the protein PBP1 bacteria in a molecular docking. The chemical's carbonyl group was demonstrated to show a substantial role in antibacterial application; out of seven contacts, the carbonyl group made five bonds with the bacteria's main protein (Van der Waals bond and four good hydrogen bonds). This high bind energy was computed (-6.9 kcal/mol) indicating considerable antibacterial action.

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Journal articles on the topic 'Propanal Spectra'

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